1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Ingenic JZ4780 DMA controller 4 * 5 * Copyright (c) 2015 Imagination Technologies 6 * Author: Alex Smith <alex@alex-smith.me.uk> 7 */ 8 9 #include <linux/clk.h> 10 #include <linux/dmapool.h> 11 #include <linux/init.h> 12 #include <linux/interrupt.h> 13 #include <linux/module.h> 14 #include <linux/of.h> 15 #include <linux/of_device.h> 16 #include <linux/of_dma.h> 17 #include <linux/platform_device.h> 18 #include <linux/slab.h> 19 20 #include "dmaengine.h" 21 #include "virt-dma.h" 22 23 /* Global registers. */ 24 #define JZ_DMA_REG_DMAC 0x00 25 #define JZ_DMA_REG_DIRQP 0x04 26 #define JZ_DMA_REG_DDR 0x08 27 #define JZ_DMA_REG_DDRS 0x0c 28 #define JZ_DMA_REG_DCKE 0x10 29 #define JZ_DMA_REG_DCKES 0x14 30 #define JZ_DMA_REG_DCKEC 0x18 31 #define JZ_DMA_REG_DMACP 0x1c 32 #define JZ_DMA_REG_DSIRQP 0x20 33 #define JZ_DMA_REG_DSIRQM 0x24 34 #define JZ_DMA_REG_DCIRQP 0x28 35 #define JZ_DMA_REG_DCIRQM 0x2c 36 37 /* Per-channel registers. */ 38 #define JZ_DMA_REG_CHAN(n) (n * 0x20) 39 #define JZ_DMA_REG_DSA 0x00 40 #define JZ_DMA_REG_DTA 0x04 41 #define JZ_DMA_REG_DTC 0x08 42 #define JZ_DMA_REG_DRT 0x0c 43 #define JZ_DMA_REG_DCS 0x10 44 #define JZ_DMA_REG_DCM 0x14 45 #define JZ_DMA_REG_DDA 0x18 46 #define JZ_DMA_REG_DSD 0x1c 47 48 #define JZ_DMA_DMAC_DMAE BIT(0) 49 #define JZ_DMA_DMAC_AR BIT(2) 50 #define JZ_DMA_DMAC_HLT BIT(3) 51 #define JZ_DMA_DMAC_FAIC BIT(27) 52 #define JZ_DMA_DMAC_FMSC BIT(31) 53 54 #define JZ_DMA_DRT_AUTO 0x8 55 56 #define JZ_DMA_DCS_CTE BIT(0) 57 #define JZ_DMA_DCS_HLT BIT(2) 58 #define JZ_DMA_DCS_TT BIT(3) 59 #define JZ_DMA_DCS_AR BIT(4) 60 #define JZ_DMA_DCS_DES8 BIT(30) 61 62 #define JZ_DMA_DCM_LINK BIT(0) 63 #define JZ_DMA_DCM_TIE BIT(1) 64 #define JZ_DMA_DCM_STDE BIT(2) 65 #define JZ_DMA_DCM_TSZ_SHIFT 8 66 #define JZ_DMA_DCM_TSZ_MASK (0x7 << JZ_DMA_DCM_TSZ_SHIFT) 67 #define JZ_DMA_DCM_DP_SHIFT 12 68 #define JZ_DMA_DCM_SP_SHIFT 14 69 #define JZ_DMA_DCM_DAI BIT(22) 70 #define JZ_DMA_DCM_SAI BIT(23) 71 72 #define JZ_DMA_SIZE_4_BYTE 0x0 73 #define JZ_DMA_SIZE_1_BYTE 0x1 74 #define JZ_DMA_SIZE_2_BYTE 0x2 75 #define JZ_DMA_SIZE_16_BYTE 0x3 76 #define JZ_DMA_SIZE_32_BYTE 0x4 77 #define JZ_DMA_SIZE_64_BYTE 0x5 78 #define JZ_DMA_SIZE_128_BYTE 0x6 79 80 #define JZ_DMA_WIDTH_32_BIT 0x0 81 #define JZ_DMA_WIDTH_8_BIT 0x1 82 #define JZ_DMA_WIDTH_16_BIT 0x2 83 84 #define JZ_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ 85 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ 86 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) 87 88 #define JZ4780_DMA_CTRL_OFFSET 0x1000 89 90 /* macros for use with jz4780_dma_soc_data.flags */ 91 #define JZ_SOC_DATA_ALLOW_LEGACY_DT BIT(0) 92 #define JZ_SOC_DATA_PROGRAMMABLE_DMA BIT(1) 93 #define JZ_SOC_DATA_PER_CHAN_PM BIT(2) 94 #define JZ_SOC_DATA_NO_DCKES_DCKEC BIT(3) 95 96 /** 97 * struct jz4780_dma_hwdesc - descriptor structure read by the DMA controller. 98 * @dcm: value for the DCM (channel command) register 99 * @dsa: source address 100 * @dta: target address 101 * @dtc: transfer count (number of blocks of the transfer size specified in DCM 102 * to transfer) in the low 24 bits, offset of the next descriptor from the 103 * descriptor base address in the upper 8 bits. 104 */ 105 struct jz4780_dma_hwdesc { 106 uint32_t dcm; 107 uint32_t dsa; 108 uint32_t dta; 109 uint32_t dtc; 110 }; 111 112 /* Size of allocations for hardware descriptor blocks. */ 113 #define JZ_DMA_DESC_BLOCK_SIZE PAGE_SIZE 114 #define JZ_DMA_MAX_DESC \ 115 (JZ_DMA_DESC_BLOCK_SIZE / sizeof(struct jz4780_dma_hwdesc)) 116 117 struct jz4780_dma_desc { 118 struct virt_dma_desc vdesc; 119 120 struct jz4780_dma_hwdesc *desc; 121 dma_addr_t desc_phys; 122 unsigned int count; 123 enum dma_transaction_type type; 124 uint32_t status; 125 }; 126 127 struct jz4780_dma_chan { 128 struct virt_dma_chan vchan; 129 unsigned int id; 130 struct dma_pool *desc_pool; 131 132 uint32_t transfer_type; 133 uint32_t transfer_shift; 134 struct dma_slave_config config; 135 136 struct jz4780_dma_desc *desc; 137 unsigned int curr_hwdesc; 138 }; 139 140 struct jz4780_dma_soc_data { 141 unsigned int nb_channels; 142 unsigned int transfer_ord_max; 143 unsigned long flags; 144 }; 145 146 struct jz4780_dma_dev { 147 struct dma_device dma_device; 148 void __iomem *chn_base; 149 void __iomem *ctrl_base; 150 struct clk *clk; 151 unsigned int irq; 152 const struct jz4780_dma_soc_data *soc_data; 153 154 uint32_t chan_reserved; 155 struct jz4780_dma_chan chan[]; 156 }; 157 158 struct jz4780_dma_filter_data { 159 struct device_node *of_node; 160 uint32_t transfer_type; 161 int channel; 162 }; 163 164 static inline struct jz4780_dma_chan *to_jz4780_dma_chan(struct dma_chan *chan) 165 { 166 return container_of(chan, struct jz4780_dma_chan, vchan.chan); 167 } 168 169 static inline struct jz4780_dma_desc *to_jz4780_dma_desc( 170 struct virt_dma_desc *vdesc) 171 { 172 return container_of(vdesc, struct jz4780_dma_desc, vdesc); 173 } 174 175 static inline struct jz4780_dma_dev *jz4780_dma_chan_parent( 176 struct jz4780_dma_chan *jzchan) 177 { 178 return container_of(jzchan->vchan.chan.device, struct jz4780_dma_dev, 179 dma_device); 180 } 181 182 static inline uint32_t jz4780_dma_chn_readl(struct jz4780_dma_dev *jzdma, 183 unsigned int chn, unsigned int reg) 184 { 185 return readl(jzdma->chn_base + reg + JZ_DMA_REG_CHAN(chn)); 186 } 187 188 static inline void jz4780_dma_chn_writel(struct jz4780_dma_dev *jzdma, 189 unsigned int chn, unsigned int reg, uint32_t val) 190 { 191 writel(val, jzdma->chn_base + reg + JZ_DMA_REG_CHAN(chn)); 192 } 193 194 static inline uint32_t jz4780_dma_ctrl_readl(struct jz4780_dma_dev *jzdma, 195 unsigned int reg) 196 { 197 return readl(jzdma->ctrl_base + reg); 198 } 199 200 static inline void jz4780_dma_ctrl_writel(struct jz4780_dma_dev *jzdma, 201 unsigned int reg, uint32_t val) 202 { 203 writel(val, jzdma->ctrl_base + reg); 204 } 205 206 static inline void jz4780_dma_chan_enable(struct jz4780_dma_dev *jzdma, 207 unsigned int chn) 208 { 209 if (jzdma->soc_data->flags & JZ_SOC_DATA_PER_CHAN_PM) { 210 unsigned int reg; 211 212 if (jzdma->soc_data->flags & JZ_SOC_DATA_NO_DCKES_DCKEC) 213 reg = JZ_DMA_REG_DCKE; 214 else 215 reg = JZ_DMA_REG_DCKES; 216 217 jz4780_dma_ctrl_writel(jzdma, reg, BIT(chn)); 218 } 219 } 220 221 static inline void jz4780_dma_chan_disable(struct jz4780_dma_dev *jzdma, 222 unsigned int chn) 223 { 224 if ((jzdma->soc_data->flags & JZ_SOC_DATA_PER_CHAN_PM) && 225 !(jzdma->soc_data->flags & JZ_SOC_DATA_NO_DCKES_DCKEC)) 226 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DCKEC, BIT(chn)); 227 } 228 229 static struct jz4780_dma_desc *jz4780_dma_desc_alloc( 230 struct jz4780_dma_chan *jzchan, unsigned int count, 231 enum dma_transaction_type type) 232 { 233 struct jz4780_dma_desc *desc; 234 235 if (count > JZ_DMA_MAX_DESC) 236 return NULL; 237 238 desc = kzalloc(sizeof(*desc), GFP_NOWAIT); 239 if (!desc) 240 return NULL; 241 242 desc->desc = dma_pool_alloc(jzchan->desc_pool, GFP_NOWAIT, 243 &desc->desc_phys); 244 if (!desc->desc) { 245 kfree(desc); 246 return NULL; 247 } 248 249 desc->count = count; 250 desc->type = type; 251 return desc; 252 } 253 254 static void jz4780_dma_desc_free(struct virt_dma_desc *vdesc) 255 { 256 struct jz4780_dma_desc *desc = to_jz4780_dma_desc(vdesc); 257 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(vdesc->tx.chan); 258 259 dma_pool_free(jzchan->desc_pool, desc->desc, desc->desc_phys); 260 kfree(desc); 261 } 262 263 static uint32_t jz4780_dma_transfer_size(struct jz4780_dma_chan *jzchan, 264 unsigned long val, uint32_t *shift) 265 { 266 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 267 int ord = ffs(val) - 1; 268 269 /* 270 * 8 byte transfer sizes unsupported so fall back on 4. If it's larger 271 * than the maximum, just limit it. It is perfectly safe to fall back 272 * in this way since we won't exceed the maximum burst size supported 273 * by the device, the only effect is reduced efficiency. This is better 274 * than refusing to perform the request at all. 275 */ 276 if (ord == 3) 277 ord = 2; 278 else if (ord > jzdma->soc_data->transfer_ord_max) 279 ord = jzdma->soc_data->transfer_ord_max; 280 281 *shift = ord; 282 283 switch (ord) { 284 case 0: 285 return JZ_DMA_SIZE_1_BYTE; 286 case 1: 287 return JZ_DMA_SIZE_2_BYTE; 288 case 2: 289 return JZ_DMA_SIZE_4_BYTE; 290 case 4: 291 return JZ_DMA_SIZE_16_BYTE; 292 case 5: 293 return JZ_DMA_SIZE_32_BYTE; 294 case 6: 295 return JZ_DMA_SIZE_64_BYTE; 296 default: 297 return JZ_DMA_SIZE_128_BYTE; 298 } 299 } 300 301 static int jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan, 302 struct jz4780_dma_hwdesc *desc, dma_addr_t addr, size_t len, 303 enum dma_transfer_direction direction) 304 { 305 struct dma_slave_config *config = &jzchan->config; 306 uint32_t width, maxburst, tsz; 307 308 if (direction == DMA_MEM_TO_DEV) { 309 desc->dcm = JZ_DMA_DCM_SAI; 310 desc->dsa = addr; 311 desc->dta = config->dst_addr; 312 313 width = config->dst_addr_width; 314 maxburst = config->dst_maxburst; 315 } else { 316 desc->dcm = JZ_DMA_DCM_DAI; 317 desc->dsa = config->src_addr; 318 desc->dta = addr; 319 320 width = config->src_addr_width; 321 maxburst = config->src_maxburst; 322 } 323 324 /* 325 * This calculates the maximum transfer size that can be used with the 326 * given address, length, width and maximum burst size. The address 327 * must be aligned to the transfer size, the total length must be 328 * divisible by the transfer size, and we must not use more than the 329 * maximum burst specified by the user. 330 */ 331 tsz = jz4780_dma_transfer_size(jzchan, addr | len | (width * maxburst), 332 &jzchan->transfer_shift); 333 334 switch (width) { 335 case DMA_SLAVE_BUSWIDTH_1_BYTE: 336 case DMA_SLAVE_BUSWIDTH_2_BYTES: 337 break; 338 case DMA_SLAVE_BUSWIDTH_4_BYTES: 339 width = JZ_DMA_WIDTH_32_BIT; 340 break; 341 default: 342 return -EINVAL; 343 } 344 345 desc->dcm |= tsz << JZ_DMA_DCM_TSZ_SHIFT; 346 desc->dcm |= width << JZ_DMA_DCM_SP_SHIFT; 347 desc->dcm |= width << JZ_DMA_DCM_DP_SHIFT; 348 349 desc->dtc = len >> jzchan->transfer_shift; 350 return 0; 351 } 352 353 static struct dma_async_tx_descriptor *jz4780_dma_prep_slave_sg( 354 struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, 355 enum dma_transfer_direction direction, unsigned long flags, 356 void *context) 357 { 358 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 359 struct jz4780_dma_desc *desc; 360 unsigned int i; 361 int err; 362 363 desc = jz4780_dma_desc_alloc(jzchan, sg_len, DMA_SLAVE); 364 if (!desc) 365 return NULL; 366 367 for (i = 0; i < sg_len; i++) { 368 err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], 369 sg_dma_address(&sgl[i]), 370 sg_dma_len(&sgl[i]), 371 direction); 372 if (err < 0) { 373 jz4780_dma_desc_free(&jzchan->desc->vdesc); 374 return NULL; 375 } 376 377 desc->desc[i].dcm |= JZ_DMA_DCM_TIE; 378 379 if (i != (sg_len - 1)) { 380 /* Automatically proceeed to the next descriptor. */ 381 desc->desc[i].dcm |= JZ_DMA_DCM_LINK; 382 383 /* 384 * The upper 8 bits of the DTC field in the descriptor 385 * must be set to (offset from descriptor base of next 386 * descriptor >> 4). 387 */ 388 desc->desc[i].dtc |= 389 (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; 390 } 391 } 392 393 return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); 394 } 395 396 static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_cyclic( 397 struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, 398 size_t period_len, enum dma_transfer_direction direction, 399 unsigned long flags) 400 { 401 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 402 struct jz4780_dma_desc *desc; 403 unsigned int periods, i; 404 int err; 405 406 if (buf_len % period_len) 407 return NULL; 408 409 periods = buf_len / period_len; 410 411 desc = jz4780_dma_desc_alloc(jzchan, periods, DMA_CYCLIC); 412 if (!desc) 413 return NULL; 414 415 for (i = 0; i < periods; i++) { 416 err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], buf_addr, 417 period_len, direction); 418 if (err < 0) { 419 jz4780_dma_desc_free(&jzchan->desc->vdesc); 420 return NULL; 421 } 422 423 buf_addr += period_len; 424 425 /* 426 * Set the link bit to indicate that the controller should 427 * automatically proceed to the next descriptor. In 428 * jz4780_dma_begin(), this will be cleared if we need to issue 429 * an interrupt after each period. 430 */ 431 desc->desc[i].dcm |= JZ_DMA_DCM_TIE | JZ_DMA_DCM_LINK; 432 433 /* 434 * The upper 8 bits of the DTC field in the descriptor must be 435 * set to (offset from descriptor base of next descriptor >> 4). 436 * If this is the last descriptor, link it back to the first, 437 * i.e. leave offset set to 0, otherwise point to the next one. 438 */ 439 if (i != (periods - 1)) { 440 desc->desc[i].dtc |= 441 (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; 442 } 443 } 444 445 return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); 446 } 447 448 static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_memcpy( 449 struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, 450 size_t len, unsigned long flags) 451 { 452 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 453 struct jz4780_dma_desc *desc; 454 uint32_t tsz; 455 456 desc = jz4780_dma_desc_alloc(jzchan, 1, DMA_MEMCPY); 457 if (!desc) 458 return NULL; 459 460 tsz = jz4780_dma_transfer_size(jzchan, dest | src | len, 461 &jzchan->transfer_shift); 462 463 jzchan->transfer_type = JZ_DMA_DRT_AUTO; 464 465 desc->desc[0].dsa = src; 466 desc->desc[0].dta = dest; 467 desc->desc[0].dcm = JZ_DMA_DCM_TIE | JZ_DMA_DCM_SAI | JZ_DMA_DCM_DAI | 468 tsz << JZ_DMA_DCM_TSZ_SHIFT | 469 JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_SP_SHIFT | 470 JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_DP_SHIFT; 471 desc->desc[0].dtc = len >> jzchan->transfer_shift; 472 473 return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); 474 } 475 476 static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) 477 { 478 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 479 struct virt_dma_desc *vdesc; 480 unsigned int i; 481 dma_addr_t desc_phys; 482 483 if (!jzchan->desc) { 484 vdesc = vchan_next_desc(&jzchan->vchan); 485 if (!vdesc) 486 return; 487 488 list_del(&vdesc->node); 489 490 jzchan->desc = to_jz4780_dma_desc(vdesc); 491 jzchan->curr_hwdesc = 0; 492 493 if (jzchan->desc->type == DMA_CYCLIC && vdesc->tx.callback) { 494 /* 495 * The DMA controller doesn't support triggering an 496 * interrupt after processing each descriptor, only 497 * after processing an entire terminated list of 498 * descriptors. For a cyclic DMA setup the list of 499 * descriptors is not terminated so we can never get an 500 * interrupt. 501 * 502 * If the user requested a callback for a cyclic DMA 503 * setup then we workaround this hardware limitation 504 * here by degrading to a set of unlinked descriptors 505 * which we will submit in sequence in response to the 506 * completion of processing the previous descriptor. 507 */ 508 for (i = 0; i < jzchan->desc->count; i++) 509 jzchan->desc->desc[i].dcm &= ~JZ_DMA_DCM_LINK; 510 } 511 } else { 512 /* 513 * There is an existing transfer, therefore this must be one 514 * for which we unlinked the descriptors above. Advance to the 515 * next one in the list. 516 */ 517 jzchan->curr_hwdesc = 518 (jzchan->curr_hwdesc + 1) % jzchan->desc->count; 519 } 520 521 /* Enable the channel's clock. */ 522 jz4780_dma_chan_enable(jzdma, jzchan->id); 523 524 /* Use 4-word descriptors. */ 525 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); 526 527 /* Set transfer type. */ 528 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DRT, 529 jzchan->transfer_type); 530 531 /* 532 * Set the transfer count. This is redundant for a descriptor-driven 533 * transfer. However, there can be a delay between the transfer start 534 * time and when DTCn reg contains the new transfer count. Setting 535 * it explicitly ensures residue is computed correctly at all times. 536 */ 537 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DTC, 538 jzchan->desc->desc[jzchan->curr_hwdesc].dtc); 539 540 /* Write descriptor address and initiate descriptor fetch. */ 541 desc_phys = jzchan->desc->desc_phys + 542 (jzchan->curr_hwdesc * sizeof(*jzchan->desc->desc)); 543 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DDA, desc_phys); 544 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id)); 545 546 /* Enable the channel. */ 547 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 548 JZ_DMA_DCS_CTE); 549 } 550 551 static void jz4780_dma_issue_pending(struct dma_chan *chan) 552 { 553 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 554 unsigned long flags; 555 556 spin_lock_irqsave(&jzchan->vchan.lock, flags); 557 558 if (vchan_issue_pending(&jzchan->vchan) && !jzchan->desc) 559 jz4780_dma_begin(jzchan); 560 561 spin_unlock_irqrestore(&jzchan->vchan.lock, flags); 562 } 563 564 static int jz4780_dma_terminate_all(struct dma_chan *chan) 565 { 566 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 567 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 568 unsigned long flags; 569 LIST_HEAD(head); 570 571 spin_lock_irqsave(&jzchan->vchan.lock, flags); 572 573 /* Clear the DMA status and stop the transfer. */ 574 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); 575 if (jzchan->desc) { 576 vchan_terminate_vdesc(&jzchan->desc->vdesc); 577 jzchan->desc = NULL; 578 } 579 580 jz4780_dma_chan_disable(jzdma, jzchan->id); 581 582 vchan_get_all_descriptors(&jzchan->vchan, &head); 583 584 spin_unlock_irqrestore(&jzchan->vchan.lock, flags); 585 586 vchan_dma_desc_free_list(&jzchan->vchan, &head); 587 return 0; 588 } 589 590 static void jz4780_dma_synchronize(struct dma_chan *chan) 591 { 592 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 593 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 594 595 vchan_synchronize(&jzchan->vchan); 596 jz4780_dma_chan_disable(jzdma, jzchan->id); 597 } 598 599 static int jz4780_dma_config(struct dma_chan *chan, 600 struct dma_slave_config *config) 601 { 602 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 603 604 if ((config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES) 605 || (config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)) 606 return -EINVAL; 607 608 /* Copy the reset of the slave configuration, it is used later. */ 609 memcpy(&jzchan->config, config, sizeof(jzchan->config)); 610 611 return 0; 612 } 613 614 static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan, 615 struct jz4780_dma_desc *desc, unsigned int next_sg) 616 { 617 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 618 unsigned int count = 0; 619 unsigned int i; 620 621 for (i = next_sg; i < desc->count; i++) 622 count += desc->desc[i].dtc & GENMASK(23, 0); 623 624 if (next_sg != 0) 625 count += jz4780_dma_chn_readl(jzdma, jzchan->id, 626 JZ_DMA_REG_DTC); 627 628 return count << jzchan->transfer_shift; 629 } 630 631 static enum dma_status jz4780_dma_tx_status(struct dma_chan *chan, 632 dma_cookie_t cookie, struct dma_tx_state *txstate) 633 { 634 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 635 struct virt_dma_desc *vdesc; 636 enum dma_status status; 637 unsigned long flags; 638 unsigned long residue = 0; 639 640 status = dma_cookie_status(chan, cookie, txstate); 641 if ((status == DMA_COMPLETE) || (txstate == NULL)) 642 return status; 643 644 spin_lock_irqsave(&jzchan->vchan.lock, flags); 645 646 vdesc = vchan_find_desc(&jzchan->vchan, cookie); 647 if (vdesc) { 648 /* On the issued list, so hasn't been processed yet */ 649 residue = jz4780_dma_desc_residue(jzchan, 650 to_jz4780_dma_desc(vdesc), 0); 651 } else if (cookie == jzchan->desc->vdesc.tx.cookie) { 652 residue = jz4780_dma_desc_residue(jzchan, jzchan->desc, 653 jzchan->curr_hwdesc + 1); 654 } 655 dma_set_residue(txstate, residue); 656 657 if (vdesc && jzchan->desc && vdesc == &jzchan->desc->vdesc 658 && jzchan->desc->status & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) 659 status = DMA_ERROR; 660 661 spin_unlock_irqrestore(&jzchan->vchan.lock, flags); 662 return status; 663 } 664 665 static bool jz4780_dma_chan_irq(struct jz4780_dma_dev *jzdma, 666 struct jz4780_dma_chan *jzchan) 667 { 668 uint32_t dcs; 669 bool ack = true; 670 671 spin_lock(&jzchan->vchan.lock); 672 673 dcs = jz4780_dma_chn_readl(jzdma, jzchan->id, JZ_DMA_REG_DCS); 674 jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); 675 676 if (dcs & JZ_DMA_DCS_AR) { 677 dev_warn(&jzchan->vchan.chan.dev->device, 678 "address error (DCS=0x%x)\n", dcs); 679 } 680 681 if (dcs & JZ_DMA_DCS_HLT) { 682 dev_warn(&jzchan->vchan.chan.dev->device, 683 "channel halt (DCS=0x%x)\n", dcs); 684 } 685 686 if (jzchan->desc) { 687 jzchan->desc->status = dcs; 688 689 if ((dcs & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) == 0) { 690 if (jzchan->desc->type == DMA_CYCLIC) { 691 vchan_cyclic_callback(&jzchan->desc->vdesc); 692 693 jz4780_dma_begin(jzchan); 694 } else if (dcs & JZ_DMA_DCS_TT) { 695 vchan_cookie_complete(&jzchan->desc->vdesc); 696 jzchan->desc = NULL; 697 698 jz4780_dma_begin(jzchan); 699 } else { 700 /* False positive - continue the transfer */ 701 ack = false; 702 jz4780_dma_chn_writel(jzdma, jzchan->id, 703 JZ_DMA_REG_DCS, 704 JZ_DMA_DCS_CTE); 705 } 706 } 707 } else { 708 dev_err(&jzchan->vchan.chan.dev->device, 709 "channel IRQ with no active transfer\n"); 710 } 711 712 spin_unlock(&jzchan->vchan.lock); 713 714 return ack; 715 } 716 717 static irqreturn_t jz4780_dma_irq_handler(int irq, void *data) 718 { 719 struct jz4780_dma_dev *jzdma = data; 720 unsigned int nb_channels = jzdma->soc_data->nb_channels; 721 unsigned long pending; 722 uint32_t dmac; 723 int i; 724 725 pending = jz4780_dma_ctrl_readl(jzdma, JZ_DMA_REG_DIRQP); 726 727 for_each_set_bit(i, &pending, nb_channels) { 728 if (jz4780_dma_chan_irq(jzdma, &jzdma->chan[i])) 729 pending &= ~BIT(i); 730 } 731 732 /* Clear halt and address error status of all channels. */ 733 dmac = jz4780_dma_ctrl_readl(jzdma, JZ_DMA_REG_DMAC); 734 dmac &= ~(JZ_DMA_DMAC_HLT | JZ_DMA_DMAC_AR); 735 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC, dmac); 736 737 /* Clear interrupt pending status. */ 738 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DIRQP, pending); 739 740 return IRQ_HANDLED; 741 } 742 743 static int jz4780_dma_alloc_chan_resources(struct dma_chan *chan) 744 { 745 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 746 747 jzchan->desc_pool = dma_pool_create(dev_name(&chan->dev->device), 748 chan->device->dev, 749 JZ_DMA_DESC_BLOCK_SIZE, 750 PAGE_SIZE, 0); 751 if (!jzchan->desc_pool) { 752 dev_err(&chan->dev->device, 753 "failed to allocate descriptor pool\n"); 754 return -ENOMEM; 755 } 756 757 return 0; 758 } 759 760 static void jz4780_dma_free_chan_resources(struct dma_chan *chan) 761 { 762 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 763 764 vchan_free_chan_resources(&jzchan->vchan); 765 dma_pool_destroy(jzchan->desc_pool); 766 jzchan->desc_pool = NULL; 767 } 768 769 static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param) 770 { 771 struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); 772 struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); 773 struct jz4780_dma_filter_data *data = param; 774 775 if (jzdma->dma_device.dev->of_node != data->of_node) 776 return false; 777 778 if (data->channel > -1) { 779 if (data->channel != jzchan->id) 780 return false; 781 } else if (jzdma->chan_reserved & BIT(jzchan->id)) { 782 return false; 783 } 784 785 jzchan->transfer_type = data->transfer_type; 786 787 return true; 788 } 789 790 static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec, 791 struct of_dma *ofdma) 792 { 793 struct jz4780_dma_dev *jzdma = ofdma->of_dma_data; 794 dma_cap_mask_t mask = jzdma->dma_device.cap_mask; 795 struct jz4780_dma_filter_data data; 796 797 if (dma_spec->args_count != 2) 798 return NULL; 799 800 data.of_node = ofdma->of_node; 801 data.transfer_type = dma_spec->args[0]; 802 data.channel = dma_spec->args[1]; 803 804 if (data.channel > -1) { 805 if (data.channel >= jzdma->soc_data->nb_channels) { 806 dev_err(jzdma->dma_device.dev, 807 "device requested non-existent channel %u\n", 808 data.channel); 809 return NULL; 810 } 811 812 /* Can only select a channel marked as reserved. */ 813 if (!(jzdma->chan_reserved & BIT(data.channel))) { 814 dev_err(jzdma->dma_device.dev, 815 "device requested unreserved channel %u\n", 816 data.channel); 817 return NULL; 818 } 819 820 jzdma->chan[data.channel].transfer_type = data.transfer_type; 821 822 return dma_get_slave_channel( 823 &jzdma->chan[data.channel].vchan.chan); 824 } else { 825 return dma_request_channel(mask, jz4780_dma_filter_fn, &data); 826 } 827 } 828 829 static int jz4780_dma_probe(struct platform_device *pdev) 830 { 831 struct device *dev = &pdev->dev; 832 const struct jz4780_dma_soc_data *soc_data; 833 struct jz4780_dma_dev *jzdma; 834 struct jz4780_dma_chan *jzchan; 835 struct dma_device *dd; 836 struct resource *res; 837 int i, ret; 838 839 if (!dev->of_node) { 840 dev_err(dev, "This driver must be probed from devicetree\n"); 841 return -EINVAL; 842 } 843 844 soc_data = device_get_match_data(dev); 845 if (!soc_data) 846 return -EINVAL; 847 848 jzdma = devm_kzalloc(dev, struct_size(jzdma, chan, 849 soc_data->nb_channels), GFP_KERNEL); 850 if (!jzdma) 851 return -ENOMEM; 852 853 jzdma->soc_data = soc_data; 854 platform_set_drvdata(pdev, jzdma); 855 856 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 857 if (!res) { 858 dev_err(dev, "failed to get I/O memory\n"); 859 return -EINVAL; 860 } 861 862 jzdma->chn_base = devm_ioremap_resource(dev, res); 863 if (IS_ERR(jzdma->chn_base)) 864 return PTR_ERR(jzdma->chn_base); 865 866 res = platform_get_resource(pdev, IORESOURCE_MEM, 1); 867 if (res) { 868 jzdma->ctrl_base = devm_ioremap_resource(dev, res); 869 if (IS_ERR(jzdma->ctrl_base)) 870 return PTR_ERR(jzdma->ctrl_base); 871 } else if (soc_data->flags & JZ_SOC_DATA_ALLOW_LEGACY_DT) { 872 /* 873 * On JZ4780, if the second memory resource was not supplied, 874 * assume we're using an old devicetree, and calculate the 875 * offset to the control registers. 876 */ 877 jzdma->ctrl_base = jzdma->chn_base + JZ4780_DMA_CTRL_OFFSET; 878 } else { 879 dev_err(dev, "failed to get I/O memory\n"); 880 return -EINVAL; 881 } 882 883 ret = platform_get_irq(pdev, 0); 884 if (ret < 0) { 885 dev_err(dev, "failed to get IRQ: %d\n", ret); 886 return ret; 887 } 888 889 jzdma->irq = ret; 890 891 ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), 892 jzdma); 893 if (ret) { 894 dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); 895 return ret; 896 } 897 898 jzdma->clk = devm_clk_get(dev, NULL); 899 if (IS_ERR(jzdma->clk)) { 900 dev_err(dev, "failed to get clock\n"); 901 ret = PTR_ERR(jzdma->clk); 902 goto err_free_irq; 903 } 904 905 clk_prepare_enable(jzdma->clk); 906 907 /* Property is optional, if it doesn't exist the value will remain 0. */ 908 of_property_read_u32_index(dev->of_node, "ingenic,reserved-channels", 909 0, &jzdma->chan_reserved); 910 911 dd = &jzdma->dma_device; 912 913 dma_cap_set(DMA_MEMCPY, dd->cap_mask); 914 dma_cap_set(DMA_SLAVE, dd->cap_mask); 915 dma_cap_set(DMA_CYCLIC, dd->cap_mask); 916 917 dd->dev = dev; 918 dd->copy_align = DMAENGINE_ALIGN_4_BYTES; 919 dd->device_alloc_chan_resources = jz4780_dma_alloc_chan_resources; 920 dd->device_free_chan_resources = jz4780_dma_free_chan_resources; 921 dd->device_prep_slave_sg = jz4780_dma_prep_slave_sg; 922 dd->device_prep_dma_cyclic = jz4780_dma_prep_dma_cyclic; 923 dd->device_prep_dma_memcpy = jz4780_dma_prep_dma_memcpy; 924 dd->device_config = jz4780_dma_config; 925 dd->device_terminate_all = jz4780_dma_terminate_all; 926 dd->device_synchronize = jz4780_dma_synchronize; 927 dd->device_tx_status = jz4780_dma_tx_status; 928 dd->device_issue_pending = jz4780_dma_issue_pending; 929 dd->src_addr_widths = JZ_DMA_BUSWIDTHS; 930 dd->dst_addr_widths = JZ_DMA_BUSWIDTHS; 931 dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); 932 dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; 933 934 /* 935 * Enable DMA controller, mark all channels as not programmable. 936 * Also set the FMSC bit - it increases MSC performance, so it makes 937 * little sense not to enable it. 938 */ 939 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC, JZ_DMA_DMAC_DMAE | 940 JZ_DMA_DMAC_FAIC | JZ_DMA_DMAC_FMSC); 941 942 if (soc_data->flags & JZ_SOC_DATA_PROGRAMMABLE_DMA) 943 jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMACP, 0); 944 945 INIT_LIST_HEAD(&dd->channels); 946 947 for (i = 0; i < soc_data->nb_channels; i++) { 948 jzchan = &jzdma->chan[i]; 949 jzchan->id = i; 950 951 vchan_init(&jzchan->vchan, dd); 952 jzchan->vchan.desc_free = jz4780_dma_desc_free; 953 } 954 955 ret = dmaenginem_async_device_register(dd); 956 if (ret) { 957 dev_err(dev, "failed to register device\n"); 958 goto err_disable_clk; 959 } 960 961 /* Register with OF DMA helpers. */ 962 ret = of_dma_controller_register(dev->of_node, jz4780_of_dma_xlate, 963 jzdma); 964 if (ret) { 965 dev_err(dev, "failed to register OF DMA controller\n"); 966 goto err_disable_clk; 967 } 968 969 dev_info(dev, "JZ4780 DMA controller initialised\n"); 970 return 0; 971 972 err_disable_clk: 973 clk_disable_unprepare(jzdma->clk); 974 975 err_free_irq: 976 free_irq(jzdma->irq, jzdma); 977 return ret; 978 } 979 980 static int jz4780_dma_remove(struct platform_device *pdev) 981 { 982 struct jz4780_dma_dev *jzdma = platform_get_drvdata(pdev); 983 int i; 984 985 of_dma_controller_free(pdev->dev.of_node); 986 987 free_irq(jzdma->irq, jzdma); 988 989 for (i = 0; i < jzdma->soc_data->nb_channels; i++) 990 tasklet_kill(&jzdma->chan[i].vchan.task); 991 992 return 0; 993 } 994 995 static const struct jz4780_dma_soc_data jz4740_dma_soc_data = { 996 .nb_channels = 6, 997 .transfer_ord_max = 5, 998 }; 999 1000 static const struct jz4780_dma_soc_data jz4725b_dma_soc_data = { 1001 .nb_channels = 6, 1002 .transfer_ord_max = 5, 1003 .flags = JZ_SOC_DATA_PER_CHAN_PM | JZ_SOC_DATA_NO_DCKES_DCKEC, 1004 }; 1005 1006 static const struct jz4780_dma_soc_data jz4770_dma_soc_data = { 1007 .nb_channels = 6, 1008 .transfer_ord_max = 6, 1009 .flags = JZ_SOC_DATA_PER_CHAN_PM, 1010 }; 1011 1012 static const struct jz4780_dma_soc_data jz4780_dma_soc_data = { 1013 .nb_channels = 32, 1014 .transfer_ord_max = 7, 1015 .flags = JZ_SOC_DATA_ALLOW_LEGACY_DT | JZ_SOC_DATA_PROGRAMMABLE_DMA, 1016 }; 1017 1018 static const struct of_device_id jz4780_dma_dt_match[] = { 1019 { .compatible = "ingenic,jz4740-dma", .data = &jz4740_dma_soc_data }, 1020 { .compatible = "ingenic,jz4725b-dma", .data = &jz4725b_dma_soc_data }, 1021 { .compatible = "ingenic,jz4770-dma", .data = &jz4770_dma_soc_data }, 1022 { .compatible = "ingenic,jz4780-dma", .data = &jz4780_dma_soc_data }, 1023 {}, 1024 }; 1025 MODULE_DEVICE_TABLE(of, jz4780_dma_dt_match); 1026 1027 static struct platform_driver jz4780_dma_driver = { 1028 .probe = jz4780_dma_probe, 1029 .remove = jz4780_dma_remove, 1030 .driver = { 1031 .name = "jz4780-dma", 1032 .of_match_table = of_match_ptr(jz4780_dma_dt_match), 1033 }, 1034 }; 1035 1036 static int __init jz4780_dma_init(void) 1037 { 1038 return platform_driver_register(&jz4780_dma_driver); 1039 } 1040 subsys_initcall(jz4780_dma_init); 1041 1042 static void __exit jz4780_dma_exit(void) 1043 { 1044 platform_driver_unregister(&jz4780_dma_driver); 1045 } 1046 module_exit(jz4780_dma_exit); 1047 1048 MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>"); 1049 MODULE_DESCRIPTION("Ingenic JZ4780 DMA controller driver"); 1050 MODULE_LICENSE("GPL"); 1051